From owner-freebsd-amd64@FreeBSD.ORG  Wed Apr  6 16:00:06 2005
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Date: Wed, 06 Apr 2005 18:00:01 +0200
From: "O. Hartmann" <ohartman@mail.uni-mainz.de>
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Subject: Some questions about Winchester/Newcastle cores of Athlon64
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Dear Sirs.
In some discussions I read about some memory controler issues of
Winchester based Athlon64 cores. The CPU will downgrade to DDR333 if 4
double sided memory modules are present in a system. I also read about a
rumor nVidias nForce4 chipset is capable to handle 4 double sided memory
modules with a Winchester based CPU core, but throttling down 1T to 2T
access cycles, but remeains in DDR400 mode.
Is this also an issue of the Newcastle based CPU cores or is this a bug
in the Winchester cores?

The oncoming Venice/San Diego cores of Athlon64 CPUs are said to be
fixed and capable of driving 4 double sided memory modules.

Is this weird memory controlling behaviour also an issue on Opteron CPUs?

These questions may sound stupid, but I think many of the developers
here and hardware thugs did a lot of stuff and thaughts about this and
maybe someone is willing to answer me.

Thanks a lot in advance,
Oliver